Question: Gertrude Stein is the librettist of which opera?
Paraphrase: Gertrude Stein is the librettist of which opera?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P87 wd:Q188385 . ?sbj wdt:P31 wd:Q1344 } 
Answer: Four Saints in Three Acts, The Mother of Us All